1. Field of the Invention
This invention relates generally to orthotic devices, and more specifically to orthotic devices for use in high-heeled shoes.
The human foot may be subject to a number of abnormalities which cause pain. A number of corrective constructions have been devised for curing these problems. These corrective constructions are generally referred to in the art as "orthotics" and may be integrally formed in a shoe or adapted to be received by a shoe. Such orthotic devices commonly are used to correct abnormalities and/or to prevent foot problems or injury arising from the wearing of high-heeled dress shoes. While there has been substantial investigation by prior art workers into orthotic devices for use with athletic footwear, there has been little work into designing orthotics for reducing injury or increasing comfort of high-heeled dress shoes.
A standard high-heeled dress shoe is designed so that the heel of the foot wearing the shoe is carried higher than its toes. The height differential between the heel and the toes can vary significantly depending on the style of the shoe. It is not uncommon for heel heights to range from 11/2" to 3" or more above the toes in certain styles. Also, high-heeled shoes typically are designed with pointed toes in order to exhibit greater fashion appeal. While the design of these pointed toes also vary, it is generally common for fashion high-heeled shoes to maintain pointed toes regardless of the shape of the wearer's foot. A number of painful foot problems result from this design. For example, the downward slant of the inner sole of the shoe forces the wearer's foot to slide forward toward the toes. As the foot slides forward, the toes become jammed in the toe portion of the shoe. This can be very painful and it has been shown that at least 85% of all high-heeled shoe wearers experience such pain. Moreover, the downside slant of the inner sole places stress on the foot as the foot attempts to conform to the downward slant of the inner sole, causing the heel bone or calcaneus, to tilt downward, or plantarflex, thereby locking the first metatarsal phalangeal joint and preventing hallux extension or "toe lock". This causes the foot to pronate, greatly decreasing the overall foot comfort as well as adversely effecting the wearer's posture and ambulation all as described in U.S. Pat. No. 4,597,195 to Dananberg, one of the inventors hereof. Therefore, wearers of high-heeled shoes often complain of problems associated with toe pain, arch pain, as well as general lower back problems.
Unfortunately, no teaching exists in the prior art to construct an orthotic device that adequately corrects foot posture while permitting conventional high-heeled shoes to be worn. Typically, an orthotic device consists of several components: the heel post of rear stabilizer component located directly beneath the heel seat of the orthotic, the shell or arch accommodating section which runs from the heel to a point just behind the metatarsal heads of the foot; and the extension component that runs from a point at the end of the orthotic shell to the point where the toes join the body of the foot, commonly called the sulcus.
Richardson et al, U.S. Pat. No. 1,778,002 discloses an orthotic in which the shank is provided with extensions which are intended to act as an arch support. The shank extensions contemplated in Richardson extend laterally from the shank of the sole, extending outwardly at en acute angle with respect to the sole. The disadvantage of this construction is that it requires a sole with relatively high sides to protect or conceal Richardson's orthotic device. Moreover, the wider or higher such lateral extensions are, the more pressure may be exerted on the side or arch, vamp, foxing, and order of the shoe, thereby distorting the shape of the shoe itself.
It is also known in the prior art to provide orthotics comprising pads attached to the insole. These may take the form of metatarsal pads, midtarsal pads, or heel spur pads, such as those disclosed by Riehle et al, U.S. Pat. No. 1,867,679, Frese, Jr. in U.S. Pat. No. 2,959,875, Nalick, U.S. Pat. No. 3,777,419, and Stemmons, U.S. Pat. No. 2,075,552.
Riso et al, U.S. Pat. No. 4,250,886 discloses an orthotic for a high-heeled shoe and comprising a sole including heel and forefoot receiving portions, the heel portion being elevated approximately 11/2" about the forefoot portion. Riso's orthotic also provides a metatarsal pad secured to the sole and dimensioned so as to have one marginal edge substantially adjacent and proximal to the head of the second metatarsal, a second metatarsal edge substantially adjacent and lateral the first metatarsal and a third metatarsal edge substantially adjacent and medial to the fifth metatarsal. However, Riso requires that the orthotic position of the foot such that a constant height of 11/2" is maintained between the heel and forefoot even if the heel height exceeds 11/2". Thus, in a shoe with a standard heel height of 13/4" an orthotic made in accordance with Riso would place a 1/4" pad under the forefoot to maintain the constant 11/2" between the heel and the forefoot, and a 2" heel would require a 1/2" pad under the forefoot. The inclusion of a pad of 1/4"-1/2" thickness in a modern high-heeled shoe would crowd the wearer's toes, resulting in toe pain, and exacerbating the problem of toe lock discussed in Dananberg U.S. Pat. No. 4,597,195.